|International standard||Internet Engineering Task Force|
|Developed by||Larry Masinter|
|Introduced||April 1, 1998|
The Hyper Text Coffee Pot Control Protocol (HTCPCP) is a facetious communication protocol for controlling, monitoring, and diagnosing coffee pots. It is specified in RFC 2324, published on 1 April 1998 as an April Fools' Day RFC, as part of an April Fools prank. An extension, HTCPCP-TEA, was published as RFC 7168 on 1 April 2014 to support brewing teas, which is also an April Fools' Day RFC.
RFC 2324 was written by Larry Masinter, who describes it as a satire, saying "This has a serious purpose – it identifies many of the ways in which HTTP has been extended inappropriately." The wording of the protocol made it clear that it was not entirely serious; for example, it notes that "there is a strong, dark, rich requirement for a protocol designed espressoly [sic] for the brewing of coffee".
Despite the joking nature of its origins, or perhaps because of it, the protocol has remained as a minor presence online. The editor Emacs includes a fully functional client side implementation of it, and a number of bug reports exist complaining about Mozilla's lack of support for the protocol. Ten years after the publication of HTCPCP, the Web-Controlled Coffee Consortium (WC3) published a first draft of "HTCPCP Vocabulary in RDF" in parody of the World Wide Web Consortium's (W3C) "HTTP Vocabulary in RDF".
On April 1, 2014, RFC 7168 extended HTCPCP to fully handle teapots.
Commands and replies
HTCPCP is an extension of HTTP. HTCPCP requests are identified with the Uniform Resource Identifier (URI) scheme
coffee (or the corresponding word in any other of the 29 listed languages) and contain several additions to the HTTP methods:
||Causes the HTCPCP server to brew coffee. Using POST for this purpose is deprecated. A new HTTP request header field "Accept-Additions" is proposed, supporting optional additions including Cream, Whole-milk, Vanilla, Raspberry, Whisky, Aquavit, etc.|
||"Retrieves" coffee from the HTCPCP server.|
||Returns metadata about the coffee.|
||Says "when", causing the HTCPCP server to stop pouring milk into the coffee (if applicable).|
It also defines three error responses:
||The HTCPCP server is unable to provide the requested addition for some reason; the response should indicate a list of available additions. The RFC observes that "In practice, most automated coffee pots cannot currently provide additions."|
||The HTCPCP server is a teapot; the resulting entity body "may be short and stout" (a reference to the song "I'm a Little Teapot"). Demonstrations of this behaviour exist.|
||According to Mozilla Developer Documentation "A combined coffee/tea pot that is temporarily out of coffee should instead return 503", when requested to brew|
Save 418 movement
On 5 August 2017, Mark Nottingham, chairman of the IETF HTTPBIS Working Group, called for the removal of status code 418 "I'm a teapot" from the Node.js platform, a code implemented in reference to the original 418 "I'm a teapot" established in Hyper Text Coffee Pot Control Protocol. On 6 August 2017, Nottingham requested that references to 418 "I'm a teapot" be removed from the programming language Go and subsequently from Python's Requests and ASP.NET's HttpAbstractions library as well.
In response, 15-year-old developer Shane Brunswick created a website, save418.com, and established the "Save 418 Movement", asserting that references to 418 "I'm a teapot" in different projects serve as "a reminder that the underlying processes of computers are still made by humans". Brunswick's site went viral in the hours following its publishing, garnering thousands of upvotes on the social platform Reddit, and causing the mass adoption of the "#save418" Twitter hashtag he introduced on his site. Heeding the public outcry, Node.js, Go, Python's Requests, and ASP.NET's HttpAbstractions library decided against removing 418 "I'm a teapot" from their respective projects. The unanimous support from the aforementioned projects and the general public prompted Nottingham to begin the process of having 418 marked as a reserved HTTP status code, ensuring that 418 will not be replaced by an official status code for the foreseeable future.
On 5 October 2020, Python 3.9 released with an updated HTTP library including
418 IM_A_TEAPOT status code. In the corresponding pull request, the Save 418 movement was directly cited in support of adoption.
Around the time of the 2021–2022 Russo-Ukrainian crisis, the Russian military website mil.ru returned the HTTP 418 status code when accessed from outside of Russia as a DDoS attack protection measure. The change was first noticed in December of 2021.
- Reddington, Joseph, Illustrated implementation of Error 418, archived from the original on 2015-09-06, retrieved 2014-10-18
- Masinter, Larry M. (April 1998), "Request for Comments 2324", Network Working Group, IETF, archived from the original on 2012-04-04, retrieved 2012-03-20
- DeNardis, Laura (30 September 2009). Protocol Politics: The Globalization of Internet Governance. MIT Press. pp. 27ff. ISBN 978-0-262-04257-4. Retrieved 8 May 2012.
- Nazar, Imran (April 2014), "Request for Comments 7168", The Hyper Text Coffee Pot Control Protocol for Tea Efflux Appliances (HTCPCP-TEA), IETF, archived from the original on 2014-05-29, retrieved 2014-04-22
- Masinter, Larry. "IETF RFCs". Archived from the original on 2013-03-27.
- "Emacs extension: coffee.el", Emarsden, Chez, archived from the original on 2009-02-01, retrieved 2009-02-10.
- "Bug 46647 – (coffeehandler) HTCPCP not supported (RFC2324)", Bugzilla, Mozilla, archived from the original on 2011-05-14, retrieved 2005-12-21
- HTCPCP Vocabulary in RDF – WC3 RFC Draft, Chief Arabica (Web-Controlled Coffee Consortium), 1 April 2008, archived from the original on 15 May 2021, retrieved 17 March 2023 – via github
- Koch, Johannes (ed.), HTTP Vocabulary in RDF, et al, W3, archived from the original on 15 October 2009, retrieved 17 August 2009
- "A Goblin Teasmade teamaker with an implementation of Error 418". Archived from the original on 2014-12-06. Retrieved 2014-07-26.
- "418 I'm a teapot - HTTP | MDN". developer.mozilla.org. 2023-04-10. Retrieved 2023-09-21.
- Nottingham, Mark. "418 I'm A Teapot #14644". Archived from the original on 2017-08-10. Retrieved 2017-08-12 – via github.
- Nottingham, Mark. "net/http: remove support for status code 418 I'm a Teapot". Archived from the original on 2017-08-10. Retrieved 2017-08-12 – via github.
- Nottingham, Mark. "418 418 I'm a Teapot #4238". Archived from the original on 2021-05-15. Retrieved 2017-08-12 – via github.
- Nottingham, Mark. "418 I'm a Teapot #915". Archived from the original on 2019-05-10. Retrieved 2017-08-12 – via github.
- Brunswick, Shane. "We are the teapots". The Save 418 Movement. Archived from the original on 2021-05-15. Retrieved 2021-05-15.
- "HTTP Error Code 418 I'm a Teapot is about to be removed from Node. We've gotta do something. [x-post /r/webdev]". Archived from the original on 2017-08-11. Retrieved 2017-08-12 – via reddit.
- Nottingham, Mark. "Reserving 418". Archived from the original on 2017-08-13. Retrieved 2017-08-12 – via github.
- "What's New In Python 3.9 — Python 3.9.0 documentation". Python Documentation. 2020-10-05. Archived from the original on 2020-10-07. Retrieved 2020-10-08.
- "Issue 39507: http library missing HTTP status code 418 "I'm a teapot" – Python tracker". bugs.python.org. Archived from the original on 2020-10-14. Retrieved 2020-10-08.
- "Enable extra web security on a website". DreamHost. Retrieved 2022-12-18.
- "Russia appears to deploy digital defenses after DDoS attacks". The Record by Recorded Future. 2022-02-25. Retrieved 2022-02-26.
- "I Went to a Russian Website and All I Got Was This Lousy Teapot". PCMag. Retrieved 2022-02-28.
- "Russian MoD website blocked for non-Russian IPs | Hacker News".